Field of the Invention
The present invention relates to a toner for use in image-forming methods such as electrophotographic methods, electrostatic recording methods and toner jet methods, and to a method for producing toner.
Description of the Related Art
In recent years, printers and copiers are being subjected to demands for smaller size and longer operating lives. Now that they are being used in a variety of environments, moreover, they are also required to have improved storage stability under high-temperature conditions. An effective way to reduce the size of a device is to increase the tinting strength of a toner. Because an image can be formed with a small amount of toner by increasing the tinting strength, the toner container can be smaller. An effective means of increasing the tinting strength of a toner is to finely disperse the pigment. Pigments are being surface treated as a means of improving pigment dispersibility. Japanese Patent Application Publication No. 2012-133192 describes an example using a pigment that has been surface treated.
However, using only a surface-treated pigment such as that described in Japanese Patent Application Publication No. 2012-133192, adequate dispersibility may not be obtained, and tinting strength may not be obtained at a high level. Japanese Patent Application Publication No. 2005-181835 suggests the possibility that a higher level of tinting strength could be obtained by using a pigment dispersant that makes use of acid-base interactions.
Further, an effective means of achieving longer operating lives and heat-resistant storability is to improve the durability and heat-resistant storability of the toner. Japanese Patent Application Publication No. 2015-125406 describes an example using a polar resin with a high glass transition temperature, and research is being performed aimed at improving durability and heat-resistant storability.